This invention relates to a dishwasher having a single unit motor-pump assembly which is adapted to be installed downwardly through the bottom of the wash chamber. More specifically, it relates to the means for providing a fluid-tight seal between the pump and motor assembly and the wash chamber bottom, after the pump-motor assembly is installed.
Conventional automatic domestic dishwashers are generally provided with a pump-motor arrangement disposed entirely below the level of the bottom of the wash chamber of the dishwasher. This requires a substantially large service area below the wash chamber to permit access to the pump and motor and other related components. It has been found desirable to enlarge the capacity of the wash chamber of a dishwasher while maintaining the overall vertical dimensions of the machine in keeping with normal countertop heights and without expanding the width or depth of the cabinet beyond conventional dimensions. One way to increase the size of the wash chamber in the dishwashing machine is to expand it vertically by lowering the bottom. This, however, results in there being less space for the motor and pump arrangement to be located therebelow.
It has been found to be feasible, however, to provide that the pump and motor unit protrude upwardly through the bottom of the dishwasher tub into the wash chamber, thus allowing maximum tub size. This end can be accomplished by providing a flexible boot or shroud such as that shown in U.S. Pat. No. 3,825,373. There are, however, problems with providing an effective, inexpensive, reliable seal between the shroud and the tub bottom.